An efficient copper-catalyzed decarboxylative cross coupling reaction of coumarin 3-carboxylic acid with 4-thiazolidinones has been developed. The described strategy operated smoothly via subsequent decarboxylation and radical addition in the presence of copper catalyst and oxidant. Various coumarinyl-4-thiazolidinone derivatives were obtained easily in moderate to good yield by employing this strategy. Substrate scope and optimization have been carried out appropriately. Optimization was carried out through various copper catalyst, oxidants, and additives.